1. Ayaka Nishimura
15/Feb/2010
Geoscience P.3
Investigation of Wind Energy
Introduction:
The research question investigated was: How do the different sizes of the wind blade
affect the amount of electricity it produces? The effect of different sizes to the amount of
electricity it produces will be investigated.
Renewable energy is energy produced from natural resources such as sunlight, wind,
biofuel, rain, tides, and geothermal heat, which are renewable, naturally supplied. In this lab, the
renewable energy of wind will be investigated. Wind energy is a converted form of solar energy.
The radiation of the sun heats different parts of the earth at different rates, especially during the
day and night, and also it depends on different surfaces, such as water and land because land
absorbs sun’s radiation but water reflects it at different rates. Then different parts of the
atmosphere get warm differently. The hot air rises, so the atmospheric pressure at the earth's
surface goes down, and then cooler air is pulled in when the hot air rises. This moving air is
called wind.
Energy is the ability of a physical system to do work. Energy exists in some forms such
as heat, kinetic or mechanical energy, light, potential energy, electrical, or other forms. Potential
energy is the capacity of a system to perform work due to its position or internal structure. One
kind of potential energy is gravitational potential energy and it is a stored energy that is
determined by an object's position in a gravitational field, such as a boulder sitting at the top of a
mountain and water behind a dam, while elastic potential energy is the potential energy that is
stored in a spring. Kinetic energy is a form of energy that is energy of motion, such as a moving
car or a dropping ball. Kinetic energy has a magnitude but not a direction, so it is always positive.
There is a law about energy that is called the law of Conservation of Energy, and it means that
energy cannot be created or destroyed; it can only be converted from one form to another. The
only thing that can happen to energy in a closed system is that it can change form, such as
chemical energy can become kinetic energy. This is important to know that when energy is

2. transformed it is conserved in quantity but not in quality because it means the energy will change
to different kinds of energy so it is not focused energy like before transformation. The primary
energy transformation for most energy resources is heat. Using energy makes citizens’ lives
more convenient, such as transportation, cooking, and comfortable homes by temperature control.
So far most energy comes from non-renewable resources such as oil and coal. Citizens must save
energy by using only what they need and not wasting it. They should appliances that use little
energy. This will make resources last longer. Energy use impacts on the environment by air
pollution by automobile and factory exhaust. That causes global warming and also acid rain
which kills fish and trees.
The sun heats the water in the oceans. The earth turns so water moves like currents. It
carries warm water from equator to north. The sun evaporates water and wind carries it. Then
that water vapor falls in snow and rain. The sun also heats air and hot air rises so it makes wind
and big storms like hurricanes. Hurricanes’ energy comes from ocean heat so hurricanes bring
heat to north. Wind and water cycles bring heat all over the earth.
The sun helps plants trap energy by photosynthesis which is how plants use sunlight to
change carbon dioxide and water into glucose and oxygen that animals and people breathe.
Herbivores eat sun’s energy trapped in plants. Then secondary consumers eat primary consumers.
One food chain usually has only three or four links because about 90% of energy is lost level to
level as heat. Primary consumers are many and each level has fewer numbers because energy is
lost at each level so top of food chain has only a few animals. Humans use this energy by eating
meat and vegetables and fruits which all got their energy from sun directly like plants or
indirectly by animals.
The hypothesis was: A bigger wind blades produce more amount of electricity than
smaller wind blades, because larger wind blades catch more wind so they move faster to make
more electricity. The independent variable is different size of wind blades, and the dependent
variable is amount of electricity it produces. Controlled variables include the same time of date,
temperature of room, temperature of wind and shape of wind blade.

3. Material:
Air conditioner
Hard paper
Glue gun
Ruler
Cutter
20 Wood sticks
Multi meter
5 corks
motor
Procedure:
1. Draw 5 different sizes (8x2,10x4,9x3,11x5 and 12x6)of rectangles (5 each)on hard paper
by using a ruler
2. Cut all the rectangles on the hard paper by using a cutter
3. Stick each rectangular hard paper on a wood stick by using glue gun
4. Embed the sticks with rectangular hard paper (4 each) in a cork by using glue gun
5. Stick a motor of the multi meter into center of the wind blade and place it in front of an
air conditioner
6. Measure the amount of electricity the wind blade produces (2 times for each wind blade)

4. Data Processing and presentation:
Amount
of Electricity
(mill volt)
Model
Trial 1 Trial 2 Trial 3 Average uncertainty
1 (2x8)
16cm2
53 50 54 52 ± 2
2 (3x9)
27cm2
55 57 60 57 ± 2.5
3 (4x10)
40cm2
19 20 18 19 ± 1
4 (5x11)
55cm2
61 59 59 60 ± 0.5
5 (6x12)
72cm2
73 79 77 76 ± 3
Table1. The amount of electricity (mill volt) produced with 5 different sizes of wind blades.
Model 5, the biggest wind blade, produces on average 26 mill volts which is the most electricity
Sample Calculation:
Sum of the number of all 3 trials / number of trials
(53 + 50 + 54) / 3 = 52.3
The average amount of electricity the wind blades of model 1 produced = 52 voltmeter
Subtract the lowest number from the highest number /2
(54 - 50) / 2 = 2
The uncertainty of the wind blade model 1 is ± 2
Multiplication of the number of length and width of the wind blade
2 x 8 = 16
The area of wind blade model 1 is 16 cm2

5. Figure1.
Figure1. This graph shows good result because most of the points except 2 are on the same line.
It shows the constant increase of the amount of electricity as the area of wind blades increased.
The outlier was not included because it is obvious that it has a mistake.
Conclusion and Evaluation:
The results showed that the wind blades that has bigger size of blade produces more
amount of electricity than the wind blades that has smaller size of blade. Thus, the results
support the prediction that the bigger wind blades produce more amount of electricity than
smaller wind blades. The reason for this is because the area of the big blade can catch more wind
than small blade so it can turn faster because of catching more wind energy and this makes more
electricity.

6. The main error is that since some of the blades were not embedded in the same angle as
others, so some blades did not work well. The way to solve this problem is to make sure that all
the blades are embedded in the same angle. Another error is, since the cork of model 3 has some
big holes, the motor was not stuck into the cork. A possible solution to this problem would be to
use the cork that has no big holes in it. Temperature of the room was also possible error because
air conditioners depend on how long they are turned on and how hot outside is and also how
many people in the room. This may cause some small errors because temperature each time
maybe is not exactly the same. This error is difficult to correct so best solution is do as many
tests as possible to get accurate data.
http://physics.about.com/od/glossary/g/energy.htm
http://physics.about.com/od/glossary/g/potentialenergy.htm
http://answers.yahoo.com/question/index?qid=20081111181645AAt54g6
http://physics.about.com/od/energyworkpower/f/KineticEnergy.htm
www.virtualsciencefair.org/2006/wong6j2/definitions.html
http://www.kidzone.ws/WATER/
http://en.wikipedia.org/wiki/Energy_flow
http://en.wikipedia.org/wiki/Renewable_energy
http://en.wikipedia.org/wiki/Conservation_of_energy